274 ISLAND LIFE pakt ii 



We find also, that these great distances do not prevent 

 the immigration, of some insects of most of the orders, and 

 especially of a considerable number and variety of beetles ; 

 while even land-shells are fairly represented in both islands, 

 the large joroportion of peculiar species clearly indicating 

 that, as we might expect, individuals of this group of 

 organisms arrive only at long and irregular intervals. 



Plants are represented by a considerable variety of orders 

 and genera, most of which show some special adaptation 

 for dispersal by wind or water, or through the medium of 

 birds ; and there is no reason to doubt that besides the 

 species that have actually established themselves, many 

 others must have reached the islands, but were either not 

 suited to the climate and other physical conditions, or did 

 not find the insects necessary to their fertilisation, and 

 were therefore unable to maintain themselves. 



If now we consider the extreme remoteness and isolation 

 of these islands, their small area and comparatively recent 

 origin, and that, notwithstanding all these disadvantages, 

 they have acquired a very considerable and varied flora 

 and fauna, we shall, I think, be convinced, that with a 

 larger area and greater antiquity, mere separation from a 

 continent by many hundred miles of sea would not prevent 

 a country from acquiring a very luxuriant and varied flora, 

 and a fauna also rich and peculiar as regards all classes 

 except terrestrial mammals, amphibia, and some groups of 

 reptiles. This conclusion will be of great imj^ortance in 

 those cases where the evidence as to the exact origin of 

 the fauna and flora of an island is less clear and satisfactory 

 than in the case of the Azores and Bermuda. 



